| Abstract
| - The differences in chemical shift anisotropies, dipolar couplings, and quadrupolar couplings of two enantiomersin the chiral liquid crystalline media are employed to visualize enantiomers. In spite of the fact that protonhas high magnetic moment and is abundantly present in all the chiral molecules, 1H NMR is not exploited toits full potential because of severe overlap of unresolved transitions arising from long- and short-distancecouplings. Furthermore, the two spectra from R and S enantiomers result in doubling of the number ofobservable transitions. The present study demonstrates the application of the selectively excited homonucleardouble quantum (DQ) coherence correlated to its single quantum coherence of an isolated methyl group ina chiral molecule. The DQ dimension retains only the passive couplings within the protons of the methylgroup while the long-distance passive couplings are refocused, removing the overlap of central transitions,and each enantiomer displays a doublet instead of a triplet unlike in regular selective refocusing experiment.The doublet separation being different for each enantiomer results in their discrimination. The cross sectiontaken along the single quantum dimension pertaining to each transition in the DQ dimension provides theone-dimensional spectra for each individual enantiomer with the complete removal of the overlapped transitionsfrom the other enantiomer. The experiment is robust, the pulse sequence is easy to implement, and themethodology has been demonstrated on different chiral molecules.
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